@charset "utf-8";
body { margin: 0;font-family: sans-serif;}
h1 {font-style: italic;color: red;}
/* 网格布局 */
main {
  display: grid;
  grid-template-columns: 3fr 1fr;
  column-gap: 20px;
}
article {
  display: grid;
  grid-template-columns: 3fr 1fr;
  column-gap: 20px;
  margin: 1em;
  text-align: left;
}
.related {
  background-color: rgba(79, 185, 227, 0.3);
  border: 1px solid rgb(79, 185, 227);
  padding: 10px;
}
.sidebar,footer {
  background-color: rgba(207, 232, 220, 0.5);
  padding: 10px;
}